Booker Creek Working Group issues final report

GOVERNMENT

By Michelle Cassell
Assignment Editor

CHAPEL HILL — Chapel Hill’s Booker Creek Working Group formally approved its final recommendations report last week, as Chapel Hill Town Council requested more than a year ago.

Originally scheduled to be presented early last fall, the group has finished creating recommendations to shift the town’s stormwater goal from preventing flooding to incorporating a broader range of measures.

In 2015, Chapel Hill’s public works department began to study watersheds within town limits. The studies aimed to identify and recommend measures to prevent flooding, stabilize streams and improve overall water quality.

The Booker Creek Watershed has a drainage area of about 6.3 square miles and includes five sub-watersheds:

The town completed constructing the first project identified by the Lower Booker Creek study in 2021. Formerly called Elliott Flood Storage, the Booker Creek Basin Park is between Eastgate Crossing Shopping Center and South Elliott Road.

In September 2021, after receiving feedback from the community, the Chapel Hill Town Council approved the creation of the Booker Creek Working Group. It withdrew support for the remaining flood storage projects from the Lower Booker Creek Subwatershed study.

Working group co-chair John Morris explained that the group began their work by looking at the goals of the original projects. The group’s review concluded that there would be “minimal benefits.” An example provided by Morris was the most expensive of the six projects at Willow Drive.

“It was going to cost $4.6 million. It also had a big environmental impact because it would cut out 15 acres of forest,” Morris said.“Along Willow Drive, there are 26 structures that are in the 25-year floodplain. And this $4.6 million project, with the loss of 15 acres of forest, would mean that only three of those would no longer be in the floodplain.”

Another example the group found was on North Lakeshore Drive, near the upper end of Eastwood Lake. If the road floods there during a 25-year storm to a depth of .51 feet. Three storage projects were upstream from the location:  New Parkside Drive, Martin Luther King, and Piney Mountain. Those had a total cost of about $10 million, and they would also result in 16 acres of forest being lost.

The three storage projects would reduce the flood level on Lakeshore Drive by  one-tenth of a foot but still leave an impassable depth of water on the roadway.

“So that’s still hazardous and still impassable,” Morris said. “The bottom line was that for $10 million and 16 acres of lost forest, they would have achieved a minimal reduction in flooding and still been hazardous.”

Morris said his experience with the U.S. Army Corps of Engineers taught him projects need reconnaissance and feasibility studies to ensure projects are worthwhile.

“It was really a once-over lightly. And so they left out certain costs like land rights, design work, and utility relocations,” Morris said of the initial assessment by the town. “Those can be major costs. Some of the unbuilt basins had potential problems like major sewer line relocation and electric power line relocation, which could cost millions of dollars.”

The group concluded in the report that the town can not solve flood damage simply by controlling stormwater, and needs a broader array of tools.

“With that in mind, we brought very progressive local governments in North Carolina to tell us how they do these things,” Morris said.

One measure, that the town is already applying, is regulating new development to reduce stormwater runoff from sites. When somebody builds a big development, they must have a stormwater plan.

Municipalities can also manage their floodplains. This could include floodplain zoning, not allowing building in a flood hazard area, and buying flood-prone land for open space and parks.

The town could focus on flood-proofing structures themselves. According to the report, some buildings can be elevated so they’re out of harm’s way, or you can have buyouts of buildings in the floodplain just to get them out of danger. There are more involved measures like dams, levees and additional detention ponds as well.

The report provides ten recommendations in total, and the council is expected to guide staff on the next steps this fall.

“We can be confident in our recommendations,” Morris said. We have based our recommendations on some of the most effective and progressive programs that are in action in North Carolina. What we’re recommending is not theoretical. It’s actually programs that are proven in practice by our neighbors.”

Morris said the final report will be presented to the town council at its June 21 meeting.